<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
  <b>这是粗体字</b><br>
  <em>这是着重字</em><br>
  <i>这是斜体字</i><br>
  <small>这是小号字</small><br>
  <strong>这是加重语气</strong><br>
  <sub>这是下标字</sub><br>
  <br>
  <sup>这是上标字</sup>
</body>
</html>